The present invention relates to an improved electrical connector, for preventing male and female housings from being fitted in a misaligned manner.
An example of a conventional waterproof connector is described in JP-6-5150. As shown in FIG. 7 of this specification, this connector has a female housing 4 provided with a large hood member 3 surrounding a female terminal housing 2 which houses female terminal fittings 1, and a male housing 8 having a small hood member 7 provided at an anterior face of a male terminal housing 6 which houses male terminal fittings 5. Tabs 5A of the male terminal fittings 5 protrude in an anterior direction. When a sealing ring 9 is in a fitted state around an outer circumference of the female terminal housing 2, the small hood member 7 of the male housing 8 fits within the large hood member 3 of the female housing 4. The sealing ring 9 is pressed between the small hood member 7 and the female terminal housing 2, a seal thereby being maintained between the two housings 4 and 8.
In other words, a waterproof connector is usually configured so as to have a large hood member 3 on the female housing 4, and to have a small hood member 7 on the male housing 8, this small hood member 7 fitting between the large hood member 3 and the female terminal housing 2.
However, when such female and male housings 4 and 8 are fitted together, the male housing 8 may be fitted in a state whereby the male housing 8 is inclined relative to the female housing 4. That is, fitting may occur in a misaligned state. In that case, one edge of the small hood member 7 enters the large hood member 3 first. Conventional connectors, as in the example described above, have a configuration whereby the small hood member 7 of the male housing 8 fits between the female terminal housing 2 and the large hood member 3 of the female housing 4. As a result of this configuration, an initial misaligning of position will correct itself naturally as fitting progresses. Consequently, not much misalignment occurs during fitting. At most, either the housing 4 or the housing 8 needs to be provided with ribs and grooves to prevent upside-down fitting.
However, there may be cases where the male and female housings need to be reversed from the conventional example. In that case, as shown in schematic form in FIG. 8 (A), of this specification, a male housing d and a female housing g are provided. The male housing d has a large hood member c surrounding a male terminal housing b which houses male terminal fittings, tabs a of these male terminal fittings protruding in an anterior direction. The female housing g has a small hood member f surrounding a female terminal housing e which houses female terminal fittings. This small hood member f fits between the male terminal housing b and the large hood member c.
In this type of connector, the position of the small hood member f of the female housing g which is fitted within the large hood member c is not corrected when the two housings d and g are fitted together. Consequently, as shown in FIG. 8(B), the small hood member f can be fitted in an inclined position. In particular, when the hood members c and f are approximately rectangular, and longer sides of the small hood member f are angled so that both ends thereof are misaligned in an anterior-posterior direction, the end which is misaligned at the anterior of the small hood member f (the left end in FIG. 8(B), can easily enter deeply into the large hood member c and strike against the tabs a of the male terminal fittings which are protruding within this large hood member c, thereby causing them to change shape.
Moreover, there are non-waterproof connectors in which a female housing is fitted into a hood member of a male housing. However, in this type of connector as well, if the female housing is fitted in an inclined state, an end of longer sides of this female housing can enter deeply into the hood member and may interfere with the tabs of the male terminal fittings.
The present invention has taken the above problem into consideration, and aims to present a connector in which the misaligning of female and male housings is prevented when these are being fitted together.
According to the invention there is provided an electrical connector comprising a male housing and a female housing, the male housing having protruding male terminals and a surrounding male hood, and the female housing having female terminals adapted to receive the male terminals, the female housing being adapted to be closely received within said male hood in a fitting direction, characterised in that the female housing has external ribs extending in said fitting direction, and the male hood has corresponding grooves on the interior thereof, said ribs and grooves interengaging on mutual fitting of the male and female housings, and the female housing having four sides, said ribs being distributed around the female housing adjacent the ends of said sides.
Such an arrangement ensures that the protruding ribs contact the mouth of the male hood, and prevent damage to the male terminals by restricting the degree of misaligned insertion.
In a preferred embodiment the female housing is substantially rectangular in transverse section, the ribs being located adjacent the corners, which may be rounded. In this embodiment the ribs extend in two mutually opposite directions.
Alternatively, the female housing may be circular, and the ribs may be equi-spaced around the periphery thereof.
The female housing may have a hood for close fitting insertion into the male hood, and the ribs may be provided on the periphery of the female hood. In this embodiment a waterproofing seal is preferably provided between a female hood and the male housing when the housings are fully engaged.
The male connector may include a resilient cantilever arm latchable with a projection of the female housing.
In a preferred embodiment the arm is movable into a recess of the male housing, this recess being shielded from the mouth of the male hood in order to prevent the size thereof being unduly increased. The recess is preferably an outwardly extending portion of the male housing, and is shielded by a portion of the male hood.